Structure and functions of the ventral tube of the clover springtail Sminthurus viridis (Collembola: Sminthuridae)

Chong-Guang Chen,Bao-Zhen Hua,Tao-Ruan Wan,Tong Chen

doi:10.1038/s41598-018-37354-4

Abstract

Springtails (Collembola) are unique in Hexapoda for bearing a ventral tube (collophore) on the first abdominal segment. Although numerous studies have been conducted on the functions of the ventral tube, its fine structure has not been thoroughly elucidated to date. In this paper, we observed the jumping behavior of the clover springtail Sminthurus viridis (Linnaeus, 1758) and dissected the ventral tube using light microscopy to elucidate the fine structure and the possible function of the ventral tube. The results show that a pair of eversible vesicles can be extended from the apical opening of the ventral tube. The eversible vesicles are furnished with numerous small papillae, and can be divided into a basal part and a distal part. The eversible vesicles have a central lumen connected to the tiny papillae and leading to the body cavity. The eversible vesicles can reach any part of the body, and may serve as following functions: (a) absorbing moisture; (b) uptaking water; (c) cleaning the body surface; and (d) fastening the body on a smooth surface.

Highlights

Springtails (Collembola) are unique in Hexapoda for bearing a ventral tube on the first abdominal segment
A short ventral tube is present on the ventral side of the first abdominal segment
A pair of eversible vesicles can be extended from the distal opening of the ventral tube (Fig. 1)

Summary

Introduction

Springtails (Collembola) are unique in Hexapoda for bearing a ventral tube (collophore) on the first abdominal segment. The results show that a pair of eversible vesicles can be extended from the apical opening of the ventral tube. The functions of the ventral tube have been extensively studied[10,11,12,13,14,15,16,17,18,19,20] This organ is extremely important in fluid and electrolyte balance, but can function as a sticky appendage to enable springtails to adhere to slippery surfaces[1]. The eversible vesicles were regarded as a “cleaning” organ to clean up the body, or as a sticky appendage to enable springtails to adhere to slippery surfaces[1,2]. Most species are exceptional jumpers and some have a conspicuous ventral tube, the vesicles of which when www.nature.com/scientificreports/

Methods

Results

Conclusion